Among the early signs of liver damage, you may also find this sensation of tiredness which is felt throughout the day. One of the reasons is related to the sign above. Patients are probably not resting appropriately if their sleep/wake cycle is altered. But even if they are sleeping properly, remember that the liver is essential to regulate your energy metabolism. You could run out of glucose or stop transporting fatty acids and other nutrients effectively. In either case, the cells in your brain and the rest of your body won’t have enough raw material to work. They will become sluggish and make you feel tired.